Welding-machine.



J. H. GRAVELL. WELDING MACHINE. APPLIOATIOI FILED JAR. 17. 1913.

Patented Ocz. 7, 1913.

ATTORNEYS UNITED sTATEs PATENT oEEIoE.

.JAMES E. GRAVELL, F vPHILADILLIWHA, PENNSYLVANIA, ASSTGNOR TO HALE AND KILB'U'RN COMPANY, 0F THILADELTHIA, PENNSYLVANTA, A CORTORATION 0F DELAWARE.

Lor-ms..

Y To all whom t may concern i Philadelphia, -in .the county ci Phi-ladelphia` Beit known that I, J A11-ns H. Gawain., a citizen olf the United States, residing at and State of Pennsylvania, hase invented certain new and nsezful Improvements in TWelding-Machines, of which the following is a specitication. y

Tzhis invention 'relates to Welding machines and is directed to the provision of certain improvements in machines of this type, whereby the .performance of certain classes of Welding work is made more ccnv-enfiefnt and efficient, .and whereby :the range oit' utility .of the machine is increased.

In electric welding machines, it is nllvvays' important :that the secondary circuit he made as short as possible, :for the reason that resistance in the secondary circuit is .a very important consideration. It frequently loccurs that weld-ing Werl; is .to be done upon .articles of substantial size, such, for instance, as sheet-metal containers in the generail form of tmbs and barrels. On account of the size and shape off suclmlevices, it has been necessary heretofore to provide Welding machines with4 terminals :of substantial length so tha-t they would reach out from their support or from ythe secondary of the transformer lso far that :they )night be made to 'engage the work at the proper points. As the terminals are so extended., 'the resistance of `the secondary `circuit is increased and the operation is rendered less efficient. In some cases the size and shape of the Work are such that electric Welding is `not employed Vbecause it wouldh'e uneconomical, although on account. .fof the nature of the Work, the aise of electric Welding is highly desirablre. l

1The present invention involves the provision of terminals or fwcrkJgripiping members so shaped as to malte the machine independent of the size :and bulk lofthe articles 'to This is accomplished by the provision of a Wcrlvgripping or currentbe -We'ld'ed thereon.

carrying member which extends in one direction and is then bent backward :upon itself .to the point of engagement with the Work.'

"iD-hc opposite lWork-grepping :or currentcarrying member 1s arranged to coact with rent to and from the Work.

i-s possible@ make a lwelding machine with a Speoication yof Letters Patent.

i WELDING-MACH INE.

Patented Get. 7, 1913.

Application filed January 17, 1913. Serial No. 742,578.

secondary circuit of such small iength as to l permit of leconomical .operation .and to employ it` in .making -Welds on articles of substantial size, the construction of the .niachine itself .being independent voi the size and bulk of the device to be operated on thereby. Also, in this Way the machine is adapted for performing Welding Work which cannot be performed on Welding ma chimes of the character .heretofore commonly employed having terminals which .are substantially straight.

I have illustrated in the accompanying drawings Vthe preferred embodiment of my invention, in Whichi Figure l is a sectional .elevation partly diagrammatic of a Welding. machine constructed in vaccordance with .the invention, Fig. 2 isa top view `of .the terminals, Fig. 3 is an -end View .off the terminals, Figs. 4 and 5 are views corresponding to Fig-s. 2 and 3 and illustrating asligrhtlylmodilied form'of terminals, and Fig. 6 is a sectional elevation of .a further modified formy of terminals.

Referring Virstto Figs. l, 2 and 3, a frame or support is shown at f7., ,this bein grammatically illustrated -and inten ed to indicate a support for the terminals of .an electric welding machine constructed in any suitablemamner. Upper and lower ter-minals .are shown mounted upon the support 7, the upper terminal being vertical-lymovable dia.- y

in any suitable manner, as by means of .a

toggle 8 .and foperatinghandle 9.4 'll-he two terminals are connected in :the secondary' cir cuit of a transformer l() `whose primary is indicated atll.' The lower terminal includes a lcasting l2 of copper provided with flanges by means of which it is :bolted te the body piece 13 of the terminal. To the casting are secured twov bars let of rolled copper, these being secured :to the casting 12 by means of bolts 15. The outer ends .of the bars 14 are similarly bolted together and to a copper .bar L6 which lies between .the .hars 14 and .extends downwardly therefrom. The lower end Vof the bar 1.6 has acopper 'piece '17 bolted thereto, anden 'the end ci this .piece an integral raised vpad 18 is .p1-.ovided for acoacnion with the work. It Will he seen that the terminal 'thus nstructed .is provided with a member 14 extending vin one direction :and connected to a member 17 which yextends in the opposite direction .to the point of engagement .of .the terminal with the work. It will also be noted that there is open space between the "bars 14 beyond the casting 12. The upper `terminal is made from a casting 19 similar to the casting 12, and bars 2O similar to the bars 14.

pointed at its lower end and provided with` are bolted to the casting` and to a block 2 1 which lies between their outer ends. Itwill be noted that this construction ofI the upper terminal provides a slot extending length- Wise of the terminal between the bars 20. A

member 22 is provided in this slot adapted to be secured to the bars 2O in any position lengthwise of this slo-t. This member 22 is here shown as a cylindrical copper rod washers 23 and a nut, 24, whereby it may be secured to the bars 20 in any desired posi-I tion along the length of the slotbetween them =In Fig. 1, the work is shown as a metallic,

vessel, closed except for a 'circular opening k1n one end, and it is desired to secure a stitfening ring or reinforcement 26 to this Vessel around the opening therein. To do this, the vessel 25 is raised so that the end of the lower terminal of the machine'passes through the opening in the vessel and is.

then positioned so that the ring 26. bears upon the work-engaging pad 18 of the lower terminal and so that the edge` of'the vessel '2.5 about the opening therein bears upon the rlng. The member 22 is secured to the upper terminal in such position that it willl directly overlie the pad 18. Then, by loweringthe upper electrode, the work willbe grip ed between the member 22 and the bar 17 'o the lower terminal, whereupon the circuit may be closed and the welding current will flow through theJ parts. It will be lseen of the device to be operated upon, as, for

instance, the vessel 25. i

It hasfbeen attempted heretofore to per* formr welding work of the character indicated in Fig. 1, using a welding machine having terminals which kproject laterally from the frame of the machine throughout their length. With such a machine the welds would be made on` the side of the opening in the vessel away from'the frame of the machine., In order to operate in this i way, if the vessel be oflarge dimensions, the terminals of the machine must be made' long and the resistance of the secondary` circuit would be objectionablyl large. But with a machine constructed` as shown in Fig. 1 so that the weld may be made on the side of the opening in the vessel toward the trame of the machine, the size of the vessel to be operated onhas little or no effect upon the length required for the terminals of the machine.

In Figs. 1 and 5, a slight modificationV of the form of the terminals is shown. This differs from the construction shown in Figs. 1., 2 and 3, primarily, in that the member 22 on the upper terminal does not project through an opening in the lower terminal. Instead of this, the lower terminal has an voiset therein, so that the member may be displaced laterally from the portion of the lower terminal which isconnected to the block 13. In Fig. 5, the" lateral displace-` ment of the main portion of the lower terminal from the member 22 is clearly shown, the bar 27 which corresponds to `the bar 1.7 of Fig. 1 being of angular form so that the pad 18 thereon directly underlies the member'22. In Figs. 4 and 5, the member 22 is not shown as adjustable lengthwise of the upper terminal, as in many'cases such `adjustment would not be required. In Fig. 1, however, the member 22 is adjustable lengthwlse of the upper terminal to move it to any desired position along the slot 20. When a change in the position oit' the member 22 is made, a corresponding change is made in the bar 17 which is selected and secifr'ed to the member 16 of the lower terminal.

In Fig. 6, a further modification-ef the invention is illustrated, this differing from the vconstruction shown in Fig. 1 principallyi in that castings of copper are employed for the upper and lower terminals, instead of rolled bars.

In all of the constructions herein illustrated", it isthe lower terminal which is provided with the backwardly directed portion rather than the upper terminal. his is considered preferable for the reason that it is the common practice to make the upper terminal the movable one. It will be understood, however, that the upper terminal could be provided with a backwardly extending portion, this being of such length that its end would project under the end 'of kthe lower terminal. Such a construction,

however, would have the disadvantage that the work would be moved each time the movable terminal was moved, for the work would then be supported upon the backwardly directed end of" the ,if per terminal which end would extend un er the end of the llower terminal.

Having described vmyinventiom'f-what I claim as new therein 'and desire to 'secure by Letters Patent of the United States is:

1. A weldingmachine comprising a sup- A)ort a )air of terminals mounted thereon f away trom said support and then 1n the between which the work is gripped and between which the current passes through the work, and means for moving one of said terminals bodily in a `vertical direction upon said support, one of said terminals being so shaped that it extends laterally from the support and then backwardly toward the support, and the other terminal having a' member thereon which coacts with the backwardly extending portion 'of the Erst-named i terminal through the work, substantially as set forth.

2. A welding machine comprising a support, a pair of terminals mountedthereon between which the work is gripped and between which. the current passes through the work, one of said terminals being so shaped that it extends laterally away from said support and then backwardly toward the support, and a member mounted on the other terminal, adjustable lengthwise there ot' and extending in proximity to said backwardly extending portion of the first-named terminal, substantially as set forth.

BfA welding machine comprising a support, a pair of terminals mounted thereon between which the work is gripped and between which the current passes through the work, one ot' said terminals being so shaped that it extends laterally away from said support and then backwardly toward the support, and a member mounted on the other terminal and projecting through an opening in the portion of the first-named terminal extending from the support and in vproximity to the. backwardly extending portion thereof, substantially as set forth.

.4. A. welding machine comprising a support, a-pair of terminals mounted thereon, a transformer whose secondary is connected to said terminals, and means for moving.

one ot said terminals bodily in a Vertical direction upon said' support, one of said terminals being so shaped that the Welding i current lflows therethrough in one direction opposite direction'toward the support to the point ofl engagement of the terminal with the work and the other terminal being adapted to coact with .the first-named terminal through the work at said point of engagement with the work, substantially as set forth.

5. A welding machine comprising a transformer, two terminals connected to the secondary of the transformer and adapted to grip the work between them, one of saidterminals being so shaped that the welding current flows therethrough in one direction and then in the opposite direction to the point of engagement with the work, a member on the other terminalprojecting through an opening in the first-named terminal and in proximity to the point of engagement thereof with the work, and means for moving said terminals toward and away 'from each other, substantially as set forth.

A welding machine comprising a sup port, a pair of terminals mounted thereon between which the werk is gripped and between which the current passes through the `worlt, one ot' said terminals being so shaped that it extends laterally away from said support and then backwardly toward the support, a member mounted on the other terminal and adjustable lengthwise thereof, said member projecting through an opening in the portion of the first-named termina'l" extending trom, the support and in proximity to the bacltwardly extending portion thereof, and means for moving said terniinals toward and away from each other, substantially as set forth.

This specication signed and witnessed this 14th day ot' January, 1913.

JAMES H. GRAVELL. YWitnesses WM. J. EARNSHAW, B. TUCKER. 

